This invention is an improvement over the liquid dispensing device disclosed in U.S. Pat. No. 3,452,901, granted July 1, 1969. In this prior patent, which is expressly incorporated herein by reference, a liquid dispensing device is provided for mounting on liquid jars wherein a plunger is manually movable out of and into a liquid pump chamber from the top of the jar in order to discharge liquid therefrom. An adjustable stop is provided to limit plunger movement out of the pump chamber. A graduated liquid volume scale is provided to permit adjustment of the stop to a desired volume of liquid to be discharged in one full stroke of the plunger.
Although such a liquid dispensing device has been very satisfactory, it does require some operator judgment in aligning the stop with the desired volume as indicated on the scale since an infinite number of such positions are possible. Therefore, it is a primary object of this invention to provide an improved volume setting device which reduces the amount of operator judgment that is required for accurate volume settings.